Anticoagulant

What is Anticoagulants

When blood is collected it clots after some time. Anticoagulants are the chemicals which prevents clotting of blood when mixed with blood in proper proportion. The clotting mechanism is expressed briefly as follows

The thromboplastin released by damaged tissue or platelets converts inactive prothrombin into active thrombin in the presence of calcium ions . Thrombin converts soluble fibrinogen into insoluble fibrin clot in the presence of calcium ions.

Anticoagulants are a class of medications that are used to prevent blood clots from forming or to treat existing blood clots. Blood clots can form in the veins or arteries and can be dangerous or even life-threatening, as they can lead to heart attacks, strokes, or pulmonary embolisms.

Anticoagulants work by interfering with the body’s natural clotting process. They can do this by inhibiting the formation of blood clotting factors, preventing platelets from sticking together, or blocking the action of clotting factors already present in the blood.

Some anticoagulant such as potessium oxalate prevent clotting of blood by precipitating ionic calcium in plasma while anticoagulants such as sodium citrate convert calcium ions into unionized from.

Since calcium ions are not available blood is prevented from clotting. Heparin, however acts as antithrombin and thus prevents the formation of thrombin and blood clotting . The various anticoagulants used for routine hemoatology tests are described below .

Criteria for selection of anticoagulants

• It should efficiently prevent clotting of blood with minimum quantity .
• It should not be toxic and produce any deleterious effects on the recipient .
• It should not after any of the function of the components of the collected blood .
• It should help to increase the stability of the collected blood when stored in the refrigerator .

Types of Anticoagulants

1. Double Oxalates
2. EDTA ( Ethylene diamine tetraacetic acid , disodium or dipotassium Salt ) .
3. Heparin
4. Citrate
5. Fluoride
6. ACD
7. CPDA

Blood Group Testing

Double Oxalates Anticoagulant

3 parts of ammonium oxalate and 2 parts of potessium oxalate are combined together to balance swelling effect of ammonium oxalate and shrinking effect of potassium oxalate on the red blood cells . The solution of double Oxalate is prepared as follows

1 . Ammonium oxalate = 2.4 g

2 . Potassium oxalate = 1.6 g

3 . Distilled water = 100 ml

• 0.2 ml of this solution contains 8 mg of the chemicals which prevent clotting of about 3 to 4 ml of blood.
• 0.2 ml of this anticoagulated solution is added in each one of the bottles ( penicillin bottles ) for blood collection.
• The bottles are heated in an incubator ( or hot air oven ) at 60 – 80 ° C for about one hour.
• The bottles are taken out of incubator ( or hot air oven ) when white layer of the blood anticoagulant appear at the bottom of the bottles.

Use of Double oxalate anticoagulant

Double oxalate anticoagulant is a solution that is used to prevent blood from clotting during laboratory procedures. It is composed of two oxalates, sodium oxalate and potassium oxalate, which work together to prevent coagulation.

Sodium oxalate and potassium oxalate work by binding with calcium ions in the blood, which are necessary for clotting. When the calcium ions are bound, the blood is unable to clot. This is particularly useful in laboratory procedures where blood samples need to be stored or analyzed without clotting.

Double oxalate anticoagulant is commonly used in hematology laboratories to preserve blood samples for cell counting and analysis. It is also used in blood banks for the storage of blood and blood products.

It is important to note that double oxalate anticoagulant should not be used for coagulation tests, as it will interfere with the results. Additionally, it may cause false low results in tests that measure calcium levels in the blood.

EDTA (ethylenediaminetetraacetic acid) Anticoagulant

EDTA is a commonly used anticoagulant in blood collection tubes. It works by binding to calcium ions, which are essential for the coagulation cascade to occur. By removing calcium ions from the blood sample, EDTA prevents clotting and allows the sample to be used for diagnostic tests or other laboratory analyses.

EDTA is often used in blood tests that require whole blood samples, such as complete blood counts (CBCs) or blood chemistry tests. EDTA is also used for molecular biology experiments that require intact DNA, as it helps to prevent DNA degradation.

While EDTA is a widely used anticoagulant, it may not be suitable for all types of tests. For example, some tests require fresh whole blood samples that have not been anticoagulated, or may require a different type of anticoagulant such as heparin or citrate. Therefore, it is important to use the appropriate anticoagulant for each specific test or analysis.

It is also important to note that EDTA can cause certain changes in blood cells, such as shrinkage or swelling, which may affect the accuracy of some test results. Therefore, the laboratory performing the analysis should be aware of the anticoagulant used and any potential effects it may have on the sample.

EDTA (ethylenediaminetetraacetic acid) is a chelating agent that can bind to metal ions and remove them from solutions. It has several uses, including:

1. Medical applications: EDTA is used as a chelating agent to remove excess heavy metals such as lead, mercury, and cadmium from the body in cases of heavy metal poisoning. It is also used to treat calcific aortic stenosis and to prevent blood from clotting during blood transfusions.
2. Industrial applications: EDTA is used in various industrial processes such as detergents, oil refineries, and paper production. It helps to remove unwanted metal ions from these processes and prevent their negative effects on the final product.
3. Food and beverage applications: EDTA is used as a preservative in some food and beverage products to prevent spoilage caused by the oxidation of metal ions.
4. Laboratory applications: EDTA is commonly used as a reagent in molecular biology and biochemistry experiments to chelate metal ions and stabilize enzymes and proteins.

Heparin Anticoagulant

Heparin is a type of anticoagulant medicine this is used to prevent and deal with blood clots. It works by using binding to and activating antithrombin III, a herbal protein in the frame that inhibits blood clotting. Through enhancing the activity of antithrombin III, heparin allows to prevent the formation of blood clots and can also help to dissolve current clots.

Heparin can be given by way of injection or by way of infusion into a vein. It is regularly used inside the remedy of deep vein thrombosis (DVT), pulmonary embolism (PE), and in sufferers who are at high chance of blood clots, together with those present process sure surgeries or who’ve sure medical conditions.

There are two predominant styles of heparin: unfractionated heparin (UFH) and low molecular weight heparin (LMWH). UFH is a complex aggregate of massive and small heparin molecules and is given through injection. LMWH is a smaller, extra particular fragment of heparin and is also given by using injection.

Heparin is a effective remedy and can have severe facet consequences, consisting of bleeding, heparin-brought about thrombocytopenia (HIT), and osteoporosis. It’s miles vital to apply heparin under the steerage of a healthcare expert and in line with the prescribed dosage and tracking plan. If you have questions or issues approximately heparin, it’s far crucial to talk on your health practitioner

Heparin is often used in the following situations:

1. During surgery: Heparin may be given to prevent blood clots from forming during surgery, especially in procedures where the patient is immobilized for an extended period.
2. Treatment of deep vein thrombosis (DVT): Heparin is often used as an initial treatment for DVT, which is a blood clot that forms in a deep vein, usually in the leg.
3. Treatment of pulmonary embolism (PE): Heparin may be used to treat PE, which occurs when a blood clot blocks one of the arteries in the lungs.
4. Prevention of blood clots in people at risk: Heparin may be prescribed to people who are at high risk of developing blood clots, such as those with a history of DVT or PE, or those who have recently undergone major surgery.
5. During hemodialysis: Heparin may be used during hemodialysis, a procedure in which blood is filtered outside the body to remove waste products in people with kidney failure, to prevent blood from clotting in the dialysis machine.

Citrate Anticoagulant

Citrate anticoagulant is a type of anticoagulant medication that is commonly used in laboratory tests and blood transfusions to prevent blood from clotting. It works by binding to calcium ions in the blood, which are essential for blood clotting to occur.

Citrate anticoagulant is usually added to blood samples when they are collected for laboratory tests, such as coagulation studies or blood typing. The anticoagulant helps to keep the blood in a liquid state, which allows for accurate testing.

In blood transfusions, citrate anticoagulant is added to the donated blood to prevent clotting during storage and transport. However, after the blood is transfused into the recipient’s body, the citrate must be removed because it can cause a decrease in calcium levels and other potential complications.

Common citrate anticoagulants used in clinical settings include sodium citrate and citric acid

Fluoride Anticoagulant

Fluoride is regularly used in laboratory checks, which includes glucose and lactate measurements, to inhibit the enzymes which can damage down those molecules. This lets in for greater accurate measurements of glucose and lactate degrees within the blood.

However, if fluoride is by accident introduced to a blood sample that is being examined for coagulation, it can intervene with the effects and supply a fake indication of the patient’s clotting ability. Consequently, it’s far critical to apply the ideal anticoagulant for every sort of laboratory test.

In clinical settings, not unusual anticoagulants encompass heparin, warfarin, and direct oral anticoagulants (DOACs) inclusive of dabigatran, rivaroxaban, and apixaban. Those medicinal drugs paintings by exceptional mechanisms to prevent blood clotting and are used to deal with or prevent conditions which includes deep vein thrombosis, pulmonary embolism, stroke, and atrial traumatic inflammation.

ACD Anticoagulant

ACD stands for Acid Citrate Dextrose, that’s a sort of anticoagulant answer normally used for the renovation of whole blood and blood additives for transfusion purposes.

ACD anticoagulant works by using binding to calcium ions inside the blood, which might be essential for blood clotting to arise. This facilitates to prevent the blood from clotting and preserves the blood additives for a longer period of time.

ACD anticoagulant is an answer that carries citric acid, sodium citrate, and dextrose (glucose). The citric acid and sodium citrate act because the anticoagulant by means of binding to calcium, at the same time as the dextrose gives nutrients to the blood cells to keep them alive at some stage in storage.

ACD anticoagulant is generally utilized in blood banks and transfusion centers for the storage and preservation of crimson blood cells, platelets, and plasma. It’s also utilized in certain laboratory assessments that require complete blood or blood components because the specimen.

CPDA Anticoagulant

CPDA-1 is another type of anticoagulant solution that is commonly used for the preservation of whole blood and blood components for transfusion purposes. CPDA stands for citrate-phosphate-dextrose-adenine.

Similar to ACD, CPDA-1 works by binding to calcium ions in the blood, which prevents blood clotting and preserves the blood components for a longer period of time. The addition of adenine in CPDA-1 helps to maintain the energy metabolism of the red blood cells during storage.

CPDA-1 contains citric acid, sodium citrate, monobasic sodium phosphate, dextrose, and adenine. The citric acid and sodium citrate act as the anticoagulant by binding to calcium, while the phosphate and dextrose provide nutrients to the blood cells to keep them alive during storage. The adenine helps to maintain the energy metabolism of the red blood cells.

CPDA-1 is commonly used in blood banks and transfusion centers for the storage and preservation of red blood cells for up to 35-42 days. It is also used in certain laboratory tests that require whole blood or blood components as the specimen.

Mode of Action Anticoagulant

Anticoagulants work by interfering with one or more of the coagulation factors in the blood, which are proteins that are involved in the blood clotting process. There are several different types of anticoagulants, and each one works in a slightly different way to prevent blood clots.

Heparin and related drugs such as low molecular weight heparins (LMWH) work by binding to a protein called antithrombin III, which inactivates several coagulation factors including thrombin and Factor Xa. This prevents the formation of blood clots and is commonly used to prevent blood clots in hospitalized patients.

Warfarin and related drugs such as coumarins work by interfering with the production of vitamin K-dependent coagulation factors, which are important for blood clotting. By reducing the amount of these coagulation factors, warfarin can prevent blood clots from forming. It is commonly used to treat and prevent blood clots in patients with atrial fibrillation, deep vein thrombosis, and pulmonary embolism.

Direct oral anticoagulants (DOACs) such as dabigatran, rivaroxaban, and apixaban work by inhibiting specific coagulation factors such as thrombin or Factor Xa. These medications are designed to be more specific and have fewer drug interactions compared to older anticoagulants like warfarin.